1. Field of Invention
This invention is directed to systems, methods and structures for manipulating the airflow resulting from fluid ejector carriage motion in fluid ejection devices.
2. Description of Related Art
A variety of systems, methods, structures and/or devices are conventionally used to remove mist which is generated during the operation of fluid ejection devices, such as, for example, ink jet printers. In fluid ejection systems, mist removal is recognized as a significant problem. Very small residual droplets of fluid, such as, for example, ink in ink jet printers, are produced during the fluid ejection process. The residual droplets get caught up in the airflow generated by fluid ejector carriage motion. The residual droplets land indiscriminately, over a period of time, on internal surfaces of the fluid ejection devices. The film left by the residual droplets coats various internal surfaces of the fluid ejection device resulting in, not only cleanliness issues, but also impact to the operation of the fluid ejection device. Specifically, when the film that results from dry residual droplets accumulating on structures along which the carriage is designed to translate, such as, for example, fluid ejector carriage guide rods, the film can impede carriage motion. Additionally, accumulation on various internal sensors degrades the performance of these sensors.
The conventional solution for dealing with mist removal is to add separate, often electrically-driven, fans that can include filters. The disadvantages associated with the addition of separate fans include additional weight and/or structure, greater noise, and increased potential for failure, as well as increased cooling and energy requirements to support the additional fans and like devices.
A variety of systems, methods, structures and/or devices are conventionally used to dissipate heat in thermal fluid ejector modules of fluid ejection devices. The thermal fluid ejector modules of fluid ejection devices, such as, for example, ink jet printers, generate significant amounts of residual heat as the fluid is ejected by heating the fluid to the point of vaporization. This residual heat changes the performance, and ultimately the ejection quality, if the heat remains within the fluid ejector module. During lengthy operation or heavy coverage ejection, the temperature of the thermal fluid ejector module can exceed an allowable temperature limit. Once the temperature limit is exceeded, a slow down or cool down period is normally required to maintain ejection quality.
Many fluid ejection devices, such as, for example, printers, copiers and the like, improve throughput by improving thermal performance. Various techniques are used to remove heat from the fluid ejector module. These techniques include: diverting excess heat into the fluid being ejected; using heat sinks to conduct heat away from the fluid ejector module; and, as with residual mist removal, adding separate fans to increase the total volume of air circulating throughout the fluid ejection device facilitating additional cooling.
Improving heat transfer away from fluid ejection elements can be accomplished by directing flow of ambient air through the fluid ejector carriage and across the heater elements of the fluid ejection module housed in the carriage, and additionally across heat sinks, when installed. U.S. Pat. No. 6,382,760 to Peter, incorporated herein by reference in its entirety, discloses various exemplary embodiments of structures and/or devices for the manipulation of airflow through a fluid ejector carriage for cooling the heater elements and heat sinks.
A variety of systems, methods, structures and/or devices are conventionally used to dry the fluid deposited on a receiving medium by fluid ejection devices and/or to set certain “hot melt” fluids deposited on a receiving medium in a semi-molten state. Print quality in fluid ejection printer devices is enhanced when the fluid ejected onto the receiving medium is rapidly dried and/or set. Again here, separate fans usable to force airflow across the receiving medium have conventionally facilitated this function.
In all cases, the addition of separate fans for mist removal, fluid ejection element cooling, and receiving medium drying results in the disadvantages of additional weight, size, noise, heat production, and/or energy required in the fluid ejection device.